I put a mini-split on our 24' enclosed. Its a Senville 12k BTU, mounted on a rack I built hanging over the tongue (one side of our v-nose).
Fairly straightforward project. Had to add the AC circuitry as the trailer only had 12V. Added a battery charger when I did that.
The trailer will still need insulation. Ours is black, and the roof is at like 150F in the FL summer sun. I think it'll be sufficient once we insulate it; knocked the edge off at 95F Sebring but was better if you stood in front of it, and the heat coming off the roof radiates right to your head.
The mini-split units are cheaper, quieter, more efficient than an RV unit. And you don't need to put a giant hole in your roof.
Also consider an RV door latch so you can get out.
